It's always difficult to be objective about your own writing, because of the personal associations. Despite this, if you hope to find a publisher, you must try and write as well as you can, which includes objective assessment and often ruthless editing.

Here are some things to consider when critiquing your own or other poets' work:

Subject

If the poem is personal, does it rise above the purely individual and become more widely relevant? It's easy to forget that poetry is art, not a diary entry, nor journalism. It does not have to reflect the truth exactly as it happened. The facts are no more than raw materials and you should manipulate, adapt and polish until they fit your needs. This alteration gives you a greater chance of writing something that touches other people, rather than something that is dismissed as an adolescent angst poem.

Does the poem deal with one of the 'big' subjects like love or peace? If so, does it show a new perspective? Or is it stating what has already been said many times? It's usually better to avoid the big issues, or, at least, not to try and deal with the whole thing at once: one specific small incident or image is usually worth a lot more than overwhelming generalizations which tend to result in cliché-ridden verse.

Title

Not all poems have a title, but if they do, it should add something to the piece. The first line is useful for reference or filing purposes, but rarely works as a title. Nor should you necessarily use a direct quote from the poem. This is particularly true of short poems where the repetition of a phrase in title and poem may detract from its effectiveness.

Form and Structure

There are many formal poetry structures (sonnets, sestinas, dizains, villanelles etc), but sometimes one is more appropriate than another. A well-written sonnet, for example, is a lovely tool for putting forward two contrasting ideas or views of one subject, and then rounding off with a conclusion in the couplet. It is not, however, the ideal form for narrating a story.

Of course you don't need to use a traditional form: there's nothing wrong with free verse, if it's the best form for what you're trying to say. But do make a conscious decision: the form and content should complement each other.

Rhyme

Rhyming couplets and iambic quatrains are difficult to use for serious poetry as the idea often gets subordinated to the form, resulting in doggerel. The same is true of constant end-rhyme: it's tempting to twist the word order, or use archaic vocabulary, to force the content to fit the form.

Remember that you can use half rhyme, which is less obtrusive than full rhyme, and internal rhyme, too. And, of course, there are other sound devices such as assonance and alliteration, which can (and perhaps should) be used.

Meter

Very few people nowadays believe that verse must have a perfectly regular meter; however, it is still an important aspect of poetry. Even free verse makes use of rhythm to convey or strengthen meaning. One way to find out if your poem works metrically is to read it out loud. If you find that you have to put unnatural stress on an article or preposition, or you have to scurry to cram too many syllables in too short a space, go back and re-work it. Don't ever be satisfied with 'I can make it sound right'; ask yourself honestly if someone else could.

One more thing - don't think that slipping in an extra article, pronoun, 'and' or 'but' to make it scan is always the best solution: consider whether that syllable is really necessary. Don't pad; rewrite.

Layout and line breaks

Line breaks and verse structure don't automatically make something a poem. The breaks work together with punctuation to show the reader how the poem is to be read. Again, reading out loud is important to find the natural pauses, and the places where you need to guide the reader.

A common beginners' error is to end-stop all lines instead of using enjambment - where the grammatical sense continues beyond the line end onto the next line - which can make a big difference to the flow. In rhyming poetry enjambment can make the rhyme less obtrusive.

Poetry has been described as writing where the author has more control than the typesetter over the finished presentation. Even so, it's important to think carefully before you start using complex designs. You may think that your work looks better centered, or with every second line indented, but what does this actually add to the poem? A weak poem will not be improved by fancy layout.

Of course it can be fun to fit a piece about a mouse into the animal shape or to give it a long tail, as Lewis Carroll did, but is it more than a gimmick? Remember that poetry is, to a great extent, a verbal art form: do you really want your poem to rely on visual presentation?

Sound

I've already suggested reading out loud, but it's so important that I have no hesitation in repeating myself. The sound of poetry is fundamental, and unless you read each draft out loud again and again you cannot begin to make the best choices. By which I mean choices of vocabulary, punctuation, line breaks: they are all so tightly interwoven that they can hardly be considered separately.

Incidentally, reading out loud also helps with proof reading, which is fundamental: it's extremely irritating to see an otherwise effective poem ruined by typographic errors. If the poets care so little for their own work that they aren't prepared to use a dictionary or spell checker, why should I be interested in it?

Finally, a few more points that you need to be on the lookout for:

Clichés: 'Emerald green hills' and 'wintry winds' have been described so often that they should be avoided, as should 'poetical' words like 'heart', 'soul', 'moonlight' and 'love'. They may be fine in parody, but it's very hard to write something new and serious using such worn vocabulary.

Internally consistent images: metaphors and similes are a poet's tools, but they need to have some kind of internal logic. Consider 'the train disappeared into the tunnel like a mouse into its hole'. It's true that the tunnel entrance might be like a mouse hole, but can the train be like a mouse? It isn't shaped like a mouse, nor does it move like one. Try and be as objective as possible about your comparisons and images. Will they work for other people?

Appropriate vocabulary: you may consider that moggy, pussy, cat and feline are synonyms, but I don't think you could necessarily use them all in a serious poem.

Superfluous adjectives and adverbs: often the image comes across more effectively if the reader has to work a bit: don't use a list of adjectives where one judiciously chosen one will work as well. Each adjective tends to weaken the noun; each adverb weakens the verb.

Showing or telling: if you say 'I was happy' I have to take your word for it. If, instead, tell me the symptoms of your happiness - how you saw the world around you, how your body felt etc - I can deduce your happiness for myself and empathize with it.

Don't forget that all these factors must work together. Form, content, vocabulary, layout... all of them are part of a poem, and if used well, the whole will be greater than the sum of the parts.